A federal appeals court in Washington has upheld the dismissal of a challenge over the government’s classification of marijuana as a top-tier dangerous drug.

The advocacy group Americans for Safe Access and several individuals, including a disabled veteran, were fighting the U.S. Drug Enforcement Administration’s refusal to initiate proceedings to reclassify marijuana on the lower schedule.

Under the Controlled Substances Act of 1970, the DEA classifies marijuana as a “Schedule 1″ drug, the most restrictive designation. Federal law, the U.S. Court of Appeals for the D.C. Circuit noted, largely prohibits the production, sale and use of marijuana.

In rejecting a petition to reclassify marijuana to a lower level, the DEA said there’s “no currently accepted medical use for marijuana in the United States” and that the “limited existing clinical evidence is not adequate to warrant rescheduling” marijuana under federal law.

U.S. Justice Department lawyers argued in court papers that the enactment of state laws allowing the medical use of marijuana doesn’t “constitute the required science-based evidence” that must be shown for reclassification.

On January 22, the D.C. Circuit divided over whether the challengers have standing to fight the classification of marijuana. Senior Judge Harry Edwards and Judge Merrick Garland concluded the petitioners’ fight has legal footing. Judge Karen LeCraft Henderson disagreed.

To reclassify a drug to a lower standard, the DEA needs “adequate and well-controlled” studies showing marijuana’s medical efficacy. The appeals court sided with the DEA’s contention that studies are lacking on this front.

“We defer to the agency’s interpretation of these regulations and find that substantial evidence supports its determination that such studies do not exist,” Edwards said in the court’s ruling.

The challengers, in their petition seeking the reclassification of marijuana, presented more than 200 peer-reviewed studies that purport to show the medical benefits of marijuana. The D.C. Circuit said the challengers “singular reliance on ‘peer-reviewed’ studies misses the mark.”

The DEA, the appeals court said, interprets “adequate and well-controlled studies” to be more “scientifically rigorous” than peer-reviewed, published studies.

The “petitioners may have cited some peer–reviewed articles in support of their position, but they have not pointed to ‘adequate and well-controlled studies’ confirming the efficacy of marijuana for medicinal uses,” Edwards wrote in the court ruling.

Joseph Elford of Oakland-based Americans for Safe Access, who argued in the appeals court, wasn’t immediately reached for comment this afternoon. In court papers, Elford said there is medical evidence that marijuana is effective in the treatment of pain management, nausea and appetite loss.

“The federal government has sought and obtained a patent for the medical use of cannabinoids; yet, it claims in these proceedings that marijuana has no medical use,” Elford said in a brief in the D.C. Circuit.

The decision comes in the wake of a recent trend among voters to decriminalize marijuana. In recent months, residents of Colorado and Washington state voted to allow the use of marijuana without a doctor’s recommendation.

Officials in both states have asked the Justice Department for guidance regarding their new laws, and how they might conflict with federal drug laws.

Contact Mike Scarcella at mscarcella@alm.com.